Smart set making bed (8)
I believe the answer is:
mattress
'bed' is the definition.
(I've seen this before)
'smart set making' is the wordplay.
'making' indicates anagramming the letters.
'smart'+'set'='smartset'
'smartset' anagrammed gives 'MATTRESS'.
(Other definitions for mattress that I've seen before include "Palliasse" , "Sleeping support" , "Nap on this" , "Stuffed bag on which to sleep" , "Padded bag on which to sleep" .)